Re: [naviserver-devel] Upload Progress

[Vlad S. <vl...@cr...>]

As i see it by default nsd does not use mmaps, only for uploads, yes it 
might need to review this again, mmap for big movie/iso files is not 
appropriate and i am using nsd for those kinds of files most of the time.

Stephen Deasey wrote:
> On 1/2/06, Vlad Seryakov <vl...@cr...> wrote:
> 
>>I did very simple test, replaced write with aio_write and at the end
>>checked aio_error/aio_return, they all returned 0 so mmap should work
>>because file is synced. when i was doing aio_write i used aio_offset, so
>>each aio_write would put data into separate region on the file.
>>
>>Unfortunately i removed modified driver.c by accident, so i will have to
>>do it again but something is not right in simply replacing write with
>>aio_write and mmap. Without mmap, GetForm will have to read the file
>>manually and parse it, it makes it more complicated and still, if writes
>>are not complete we may get SIGBUS again.
>>
>>The problem i see here i cannot be sure that all writes are completed,
>>aio_error/aio_return are used to check only one last operation, not the
>>batch of writes.
> 
> 
> 
> We might have to drop mmap support anyway.  We're trying t accommodate
> large files, so we may run out of address space.
> 
> This summer I was running thttpd to serve some iso images.  I started
> getting busy errors when very little bandwidth was being used, and
> with only 3 concurrent users.  It turns out that a couple of extra
> images were published, and the users were all downloading different
> ones.  As thttpd uses mmap to read the files, the process ran out of
> address space.  It doesn't take much...
> 
> We still have to support mmap for reading in the case that a module
> calls Ns_ConContent(), but otherwise we can use read/write etc.
> 
> 
> -------------------------------------------------------
> This SF.net email is sponsored by: Splunk Inc. Do you grep through log files
> for problems?  Stop!  Download the new AJAX search engine that makes
> searching your log files as easy as surfing the  web.  DOWNLOAD SPLUNK!
> http://ads.osdn.com/?ad_idv37&alloc_id865&op=click
> _______________________________________________
> naviserver-devel mailing list
> nav...@li...
> https://lists.sourceforge.net/lists/listinfo/naviserver-devel
> 

-- 
Vlad Seryakov
571 262-8608 office
vl...@cr...
http://www.crystalballinc.com/vlad/